Various data recording and recovery schemes have been developed over the years for storage of information on a magnetic medium. One example utilizes peak detection to demodulate magnetically encoded data from a magnetic storage medium. Another example utilizes Partial Response/Maximum Likelihood (PRML) detectors, which offers an improvement in signal to noise ratio (SNR) in comparison to the peak detection approach. PRML have been widely adapted in various magnetic data storage medium in recent years. However, until recently, PRML read channels have been typically constructed with an analog to digital converter (ADC) inside the timing recovery loop, resulting in a complex integration process, which has slowed the adaptation into servo demodulation applications in tape drives.
To improve data storage density and system reliability, reference marks, such as synchronization marks and position marks, have been introduced in some of the magnetic data storage medium. Although reference marks have been successfully implemented in various magnetic storage medium, detection of the precise locations of synchronization and/or position marks can be difficult.
Therefore, there is a need for an improved mechanism for the detection of reference marks. In particular, the ability to improve the resolution of reference mark detection can enhance the performance of magnetic data storage system and make possible for effective integration of additional technology features.